WASHINGTON, Nov. 12 — A new top-secret intelligence report warns that Iraqis are losing faith in U.S.-led occupation forces, a development that is increasing support for the resistance, officials said Wednesday.

CIA AND WHITE HOUSE officials refused to confirm the existence of the report, which came to light amid urgently scheduled White House meetings with the U.S. civil administrator in Iraq, L. Paul Bremer. But two other senior U.S. officials said the report painted a worrisome picture of the political and security situation there.

The report suggests that spiraling violence and a lack of confidence in the U.S.-appointed Iraqi Governing Council may be bringing efforts to a turning point, sending more Iraqis over to the side of insurgents fighting occupation troops, two officials said on condition of anonymity.

Questioned by reporters after he met Wednesday morning with President Bush, Bremer said, “I think the situation with the Iraqi public is, frankly, not easy to quantify.”

Bremer said his provisional authority had conducted opinion polls and other assessments to take the Iraqi temperature. He said it was obvious that insurgents had been “trying to encourage the Iraqi people to believe the United States is not going to stay the course,” and he added, “I don’t think that that’s going to work.”

Asked about the increase in guerrilla attacks on coalition forces in Iraq, Sen. John McCain, R-Ariz., said Wednesday on CBS’s “The Early Show” that “these are very intelligent moves that the bad people are making. ... Time is not on our side.”

Because the report is classified, the U.S. officials declined to furnish details, talking about it only in general terms and only on the ground that they not be publicly identified.

On the subject of the increasing violence, one official noted that U.S. forces were already using more aggressive raids and other tactics to try to fight insurgents, which officials fear could alienate more Iraqis.

For instance, U.S. forces responded with aerial bombing and mortars over the weekend in a show-of-force response to the downing of a U.S. helicopter last week.

Wednesday, U.S. troops opened fire by accident on a car carrying a member of the Iraqi Governing Council, the Iraqi administration said. The council member escaped injury, but the driver was hurt.

A defense official said Wednesday that the administration worried that support of coalition partners could also wane as more international contingents suffer casualties in Iraq. He spoke after authorities reported a truck bomb attack Wednesday against the headquarters of the Italian Carabinieri police in the southern Iraqi city of Nasiriyah. The attack killed at least 25 people, including 17 Italians.

Meanwhile on the political side, the CIA report warns, appointed Iraqi leaders do not appear to be up to the job of governing or working toward holding elections, an official said.

He would not say what, if any, recommendations the CIA made in the report, which was delivered to the administration Monday.

White House press secretary Scott McClellan would not comment on the report, but he said: “There are a lot of indications to show that the Iraqi people want the coalition forces to stay and finish the job. They do not want to return to the days of a brutal, oppressive regime. They recognize that there is a better future coming for them.”

The Philadelphia Inquirer, which first reported on the CIA assessment in Wednesday’s editions, said the report found that it was impossible to completely seal Iraq’s borders against infiltration by foreign fighters. The report also raised concern that majority Shiite Muslims could begin joining minority Sunnis in turning against the occupation, the newspaper said.